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Re: Static array with #defined # of "extra" members

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Am 04.08.2012 04:05, schrieb Ian Pilcher:
> I need to create a static array of structures with the following
> characteristics:
> 
> * The first few members of the array are pre-initialized
> * The remaining members of the array are initialized to "zero"
> * The number of additional members is determined by a #defined constant,
>   independently of the number of pre-initialized members
> #define NUM_EXTRA_FOOS     5


Yes this can be done even without much preprocessor magic.

Defining your initializers in a macro

#define FIRST_ELEMS { 1 }, { 2 }, { 3 }, { 4 }, { 5 }

and then replace your struct definition by just an array where the size
expression is constructed from the sizeof of a compount literal.

struct foo all_foos[NUM_EXTRA_FOOS + sizeof((struct foo[]){
FIRST_ELEMS})/sizeof(struct foo)] = {
       FIRST_ELEMS,
       };

Preprocessor magic can also be used to generated some fixed length list
of initializers, if you prefer that, but this is a bit more involved.

Jens

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Static array with #defined # of "extra" members Ian Pilcher <arequipeno@gmail.com> - 2012-08-03 21:05 -0500
  Re: Static array with #defined # of "extra" members "China Blue [Tor], Meersburg" <chine.bleu@yahoo.com> - 2012-08-03 19:40 -0700
  Re: Static array with #defined # of "extra" members Eric Sosman <esosman@ieee-dot-org.invalid> - 2012-08-03 22:43 -0400
    Re: Static array with #defined # of "extra" members Ian Pilcher <arequipeno@gmail.com> - 2012-08-04 10:00 -0500
  Re: Static array with #defined # of "extra" members Philip Lantz <prl@canterey.us> - 2012-08-03 16:46 -1000
  Re: Static array with #defined # of "extra" members Jens Gustedt <jens.gustedt@loria.fr> - 2012-08-04 16:19 +0200

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